The die holders are designed to various specifications and dimensions. The die holders are used in swaging operations of the flexible shaft. The swaging is a process of altering a given shape into a desired shape and dimension by cold forming process using a swaging dies. The die holders are designed to achieve the different shapes and sizes to the flexible shafts to suit for various industrial applications such as automobile industry, engineering industry, construction, etc.
Various types of conventional die holders used for swaging process are known in the prior art. The U.S. Pat. No. 3,116,683 A describes the die holder. In the cited patent document, the holders are each designed to hold a number of standard individual steel stamps or type. Three embodiments are provided including a hand holder, a holder that is designed to fit into the ram of a press, and a holder which is adapted to be carried by a marking machine. The novel features of this invention are contained in each of the aforesaid three embodiments. The essential feature of each embodiment being the provision of a cavity or pocket at the lower end of the holder which is adapted to receive one or more stamp or type inserts and a novel lock plate or latch which is provided to hold one or more inserts in a predetermined fixed position in the holder. The insert(s) may be quickly changed when a different marking is required to be stamped on the next part.
The U.S. Pat. No. 6,016,682 A describes the swaging apparatus for surgical needles. In the cited patent document, the swaging apparatus includes at least a first die and a second die. The first die has a first member, which includes a first surface, and a second member, that includes a second surface. The second member is movable relative to the first member between an extended position, in which the second surface extends beyond the first surface, and a retracted position, in which the second surface does not extend beyond the first surface. The second die has at least one surface and is movable relative to the first die between a remote position and an adjacent position. When the second die moves relative to the first die from the remote position towards the adjacent position, the second member of the first die is caused to move from the extended position towards the retracted position, and the surfaces of the first and second dies cooperate with one another so as to swage a surgical needle positioned between the first and second dies. The second member of the first die is movable to the retracted position when the second die abuts the first die. In this manner, surgical needles of many different types or sizes can be swaged by the swaging apparatus.
The U.S. Pat. No. 4,995,289 A describes the die assembly having improved insert retaining system and having reversible die inserts. In the cited patent document, the die assembly comprises a die plate having one or more die inserts therein. The die plate has a recess within which the insert is positioned. The die opening in the insert extends normally of the oppositely directed major surfaces of the insert so that the insert can be reversed. The original obverse surface of the insert thus becomes the reverse surface and the original reverse surface becomes the obverse surface. The necessity of sharpening the die insert in the conventional manner is thus eliminated. Also disclosed is an improved system for mounting die inserts in a die assembly.
The U.S. Pat. No. 5,600,990 A describes the metal extrusion die stack and method. In the cited patent document, the steel extrusion apparatus includes an improved die stack with direct cone geometry. The die stack includes a die holder with removable and replaceable die inserts. The die inserts are made from a high strength material while the die holder is made of a less expensive, traditional material. A hot metal billet is extruded through an orifice provided in the die insert of the die holder. The die stack assembly is retained as an assembled unit as the extrusion container is moved out of contact with the assembly and the butt end of the metal billet is discarded. The die stack assembly is then again located on the extrusion container as a unit to begin another extrusion cycle.
The claimed die holder apparatus as described above, does not disclose the use of the re-grinded or re-sharpened inserts at the bottom of the die holders, which are treated with cryogenic or heat or sub-zero temperatures to avoid distortion in shape or profile during operating condition. Typically, the die holder apparatus does not use the packing slip when the insert face is worn out during the operations. Typically, in conventional die holders the stress developed at mounting points are high and lead to crack or breakage of slots. The claimed die holders need to be replaced when there is occurrence of chip off and clash during sliding and swaging operations.
Hence, there is need for reusable and replaceable insert mounted at the bottom of the swaging die holder, which is designed to produce required shapes or profiles and sizes for the flexible shaft to drive the seeder unit.